CITRT Notes: Virtualization

Virtualization

Rich Kowalske: How did you start?

John Dolan: Memory is key to vitalization Dual-Processor. SAN. Existing "old" hardware

Terry Chapman: Memory.

John Dolan: 4GB per "core" i.e. Dual core processor needs 8GB

Jeffrey Thompson: How much memory does ESX support?

John Dolan: 32GB? Maybe more?

Jeffrey Thompson: contrast 32-bit vs. 64-bit

John Dolan: 64-bit has tremendous gains (per Fairway/DataCore)

Jason Lee: Some Intel hardware can't support the 64-bit.

Mike Gayle: For vMotion, DRS, etc., must have *consistent* servers/processors. Buy multiple identical machines at the same time.

John Dolan: Only applies to "live" motion. Powered down systems can be moved at any time.

Mike Gold: Fiber vs. iSCSI, etc.?

Mike Gayle: Gigabit/fiber. Not pushing the extremes (not close) on SAN, processors, etc.

Mike Gayle/Mike Gold: backups are the only time the resources are stressed.

Jeffrey Thompson: Anyone vitalizing a terminal server?

Mike Gayle: yes. Works fairly well.

Jeffrey Thompson: How many users per virtual terminal server?

Mike Gayle: ~40/vserver

John Dolan: limiting users per server, but more virtual servers per physical server. Typically a DC and other stuff on each physical server

Terry Chapman: What are people vitalizing?

Mike Gayle: everything (except phone systems). Some extranet stuff not there yet, but expected. P2V works very well, BUT, it's bringing the legacy stuff (good and bad) from the old server. Building from scratch has some advantages. (if you have the media) Training and time to plan are critical. Watch performance closely during early days to learn how to tune. VMware gives lots of control, but it takes time to get it right to start with. Don't do it overnight (like FT. Lauderdale did)

John Dolan: reiterating taking time to do it right. Moving toward everything virtualized, but not there yet. Backup will remain external.

Mike Gold: Any issues with unsupported applications? (i.e., MS says don't virtualize Exchange or SQL?)

John Dolan: hasn't had anyone ask if servers are virtualized.

Jason Powell: Suggest that issues be submitted to VMware -- they will give the better support, even of the MS apps.

Mike Gayle, John Dolan confirm Jason's comments

Mike Gayle: Expect issues with dongles (license keys). Any licensing that is tied to hardware configuration is likely to be a problem, especially with vmotioning.

Jeffrey Thompson: What problems or limitations are you having with VMware?

John Dolan: VMware is "set it and forget it" until there's an upgrade. Some issues have taken long weekends. VMware has always supported well, but it's not pain free. Looking back, hard to calculate costs/savings because we're doing so much more!

Jason Powell: No real issues over the last year+. (with free server!) Started by testing on a home machine. Started with one production (test) server with TS for the MAC users. Take it slow. Having a SAN in place makes it much easier. Start there if you can. If a physical box dies, just re-point to another server.

John Dolan: If bringing in a SAN, bring in an expert to assist. SAN configuration needs expertise.

Mike Gayle: Missed consideration (and consultants were the saviors): It's very easy to blow away a server with just one click! [good test of disaster recovery] Reconsider who has the "keys to the kingdom" with rights to delete "server" files

Rich Kowalske: How many servers can run on the free version?

Jason Powell: limited by the 4GB ram limit of the old hardware. Most servers do amazingly well with 512K or 1MB

Fady Eldeiry: How much ram do you keep for the host?

Jason Powell/John Dolan: 1/2GB? With ESX, more flexible configuration

David Crist: are there applications [servers] you don't want to mix?

Jason Powell: virtualize everything. No specific consideration of the mix. Keeping backup separate is still good.

Terry Chapman: Some "small stuff" was challenging. Licensing issues, product keys.

Jeffrey Thompson: what about virtual center?

John Dolan: "really, really, like it." vMotion is great! Ability to move servers off a piece of hardware is painless. Real-world case in the past few days of a server problem and easy resolution.

Mike Gayle: Get connected with local VMware user's group! Meet the other users, but especially meet the vendors with the special products.

Jeffrey Thompson: Any use of dynamic resource scheduler? How many physical servers?

Mike Gayle: yes. (with Netware) Moves things around automatically several times a week. 3 physical servers, Dell 2950 (16GB memory each, could use that much more in each) Still not maxing CPUs

John Dolan: the issue is how much you trust it? We discovered that vMotion had already moved the servers for us from the troublesome hardware.

Bryan Johnson: procuring hardware, After vitalizing, do you work harder to match?

Mike Gayle: yes, harder to re-use those old boxes that you just freed-up -- won't work with vMotion. Put the "simple" servers on the old hardware that you can stand to be down briefly.

Jason Powell: Can you move servers back and forth between VMware server and ESX?

Dialogue: maybe. Assume yes

Chris Todd: Anyone vitalizing desktops?

Mike Gayle: looking at it. School, remote uses (way away from Ft. Lauderdale) work on virtual desktops. RDP into that theoretically dedicated desktop. Different versions of Flash are leading toward vitalizing applications for the different solutions.

Mike Gold: skeptical of virtualized desktops. Concern over performance of streaming/video, etc., so impacts productivity.

Chris Todd: Possibly using streaming applications???

Jason Powell: School environment want to have identical systems, stream everything. [ardents] Even systems with no disk!

John Dolan: Virtual Server (free) does support dongles, etc. John using VMware on top of linux instead of on top of windows. Stability over performance.

Mike Gold: Linux doesn't need all the patches of windows and requisite reboots, etc.

Bryan Johnson: what are you running for hosts?

Jason Powell: Server 2003. running for a long time…

John Dolan: means Jason hasn't patched!

Dialogue: of up-time, stability. Windows can do it (if you don't patch)

Andy Rodgers: running on older boxes keeps being mentioned.

Mike Gayle: old boxes sometimes don't suppot the cards you want to plug in - PCI express, for instance.

Jason Powell: Ease of movement lets you feel more comfortable with "disposable" hardware. If you have the data file, you still have the server. Dual-core desktop can be a good server!

Mike Gold: Moving the server file somewhere else can take some time. Must be accessible by the new server. More motivation for a SAN.

Chris Todd: compatibility issues with ESX?

John Dolan/Mike Gayle: pretty generous. Yes, limitations, but not a lot.

Mike Gayle: Network Computing just had an article, quite positive.

Bryson Medlock: Using Linux servers/samba. VMware on laptop with virtual network for testing. When done, copy over to production system.

Terry Chapman: VMware has a virtual marketplace with lots of open source tools and apps

Mike Gayle: over 300 pre-canned virtual machines available from VMware site. You don't have to set it up yourself.

Terry Chapman: majority are free!

Jason Powell: MS has a pre-configured Exchange server with 120 day trial license you can download.

Mike Gold: does MS have a P2V?

Dialogue: yes, but issues. Some issues with changing the sizes of disks.

Mike Gayle: take care to not create too large a VM -- harder to shrink than to grow.

Bryan Johnsnon/Mike Gayle: v2v is a way to shrink. Use cautiously!

Mike Gold: When should you use static vs. dynamic sizes?

Mike Gayle: lots of "best practice" info available, use your consultants! There are tradeoffs. Example: don't go VMFS for everything. Using Raw disk mode for some things for better disk performance. Backup strategy plays into the decision as well.

Bryan Johnson: From the MS perspective, it's perhaps risky to over-subscribe your disk space. MS file systems will consume the extra space. Beware "auto-grow" disks especially with Exchange

Jason Powell: best practice: turn off screen savers! Including log-in screen saver.

John Dolan: disconnect all unused peripherals (floppies, etc.)